1. Field of the Invention
This invention relates to methods and apparatus for longitudinal slicing of vegetables and fruits, and more particularly to a system and equipment for slicing large quantities of different size heads of broccoli into spears suitable for packaging and freezing.
2. Description of the Prior Art
In modern food packaging, it is often necessary to slice individual vegetables and fruits lengthwise into a plurality of spears of similar size and shape. This is particularly difficult when the vegetables or fruits are of uneven size and configuration, such as broccoli, cauliflower, and the like.
Traditionally, slicing of the vegetable or fruit into longitudinal spears has been accomplished manually by a series of workers who grasp the vegetable or fruit and wield a straight knife or cleaver to make longitudinal cuts angularly related to each other. This method of slicing the units into spears is extremely labor-intensive, and the similarity of the configuration of the spears depends in large part upon the skill of the worker.
Various machines have been proposed for reducing labor costs by eliminating manual slicing. These machines are intended to accomplish automatic slicing of the heads of broccoli and the like into a plurality of spears. Most of these machines merely quarter the head of broccoli and do not reduce the larger heads into spears small enough for freezing and packaging. The machines which do slice the broccoli heads into more than four pieces do not make the slices of similar size and shape. This is partially because the slicing blades are not accurately oriented with respect to the central longitudinal axis of the head of broccoli.
Broccoli slicing machines which grip the head of broccoli between moving resilient surfaces as they are sliced longitudinally and the butt ends of the stalks removed are shown in U.S. Pat. No. 4,455,929 issued Jun. 26, 1984 to Khosrow Goudarzi et al.; U.S. Pat. No. 3,478,794 issued Nov. 18, 1969 to Cecil W. Alpen; and U.S. Pat. No. 3,478,795 issued Nov. 18, 1969 to Herman F. Thornsbery.
Other broccoli slicing machines carry the heads of broccoli in erect position, with the flower end up, in individual pockets carried along an endless conveyor, and the heads of broccoli are sliced by a knife lowered down from above. Typical of these patents are U.S. Pat. No. 4,168,642 issued Sep. 25, 1979 to Owen H. Evans; and U.S. Pat. No. 3,695,323 issued Oct. 3, 1972 to Yngve R. Akesson et al.
Other broccoli slicing and trimming machines grasp the head of broccoli in a rotary indexing device which advances the head of broccoli to a series of circumferentially spaced stops, with cutting, slicing and trimming operations being accomplished at such stops.
Typical indexing devices are found in U.S. Pat. No. 4,658,714 issued Apr. 21, 1987 to Jack R. McIlvain et al, which grasps the head of broccoli by its flower end as it indexes the broccoli head from stop to stop, and U.S. Pat. No. 4,773,324 issued Sep. 27, 1988 to John V. Wylie et al which inverts the broccoli head and grasps it between opposed jaws at a receiving position. The head of broccoli is then indexed to a slicing device and is stopped while a pneumatic cylinder forces a multiple blade knife upwardly to slice the flower end of the head of broccoli. The head of broccoli is indexed to the next stop where a rotary knife slices off the stem end of the stalk above the gripping jaws. The broccoli is halted at still another stop where a cup-shaped, sharp rimmed cutter makes a hemispherical slice to remove the florets from the stalk. U.S. Pat. No. 3,646,977, issued Mar. 7, 1972 to Richard J. Goodale, shows a device which indexes to stopped positions and uses two separately orbiting pointed knives to stab through the broccoli and then cut down through the head.
Other patents showing apparatus for bunching broccoli and cutting off the ends, but not longitudinally slicing the broccoli, are U.S. Pat. No. 4,480,536 issued Nov. 6, 1984 to Daniel E. Burns, and U.S. Pat. No. 4,041,672 issued Aug. 16, 1977 to David L. Guarte.
The indexing machines are much too slow for high quantity production, and are very hard on both the broccoli and the machine when operated at higher speeds. I have found that each of the prior art machines discussed above, and the methods by which they operate, can be materially improved upon by the system, method and apparatus of the present invention.
The above-listed patents are believed to be relevant to the present invention because they were adduced by a prior art search made by an independent searcher, and a copy of each of the above-listed patents are supplied to the Patent and Trademark Office herewith.